This guitar is interesting from a luthiery point of view as it has a Double X Brace system which was introduced on this model in 1971. In this system, two overlapping X shapes form a diamond which surrounds the bridge plate. Some manufacturers prefer this system where additional strength is required.

Here’s a mirror image of the Double X Brace system inside this Hummingbird

For reference purposes here’s a photo of a double X brace system that I built a few years ago.

This vintage beauty is in the workshop for a set up. It becomes clear during a workbench examination that this ol’ Hummer has some problems that will need to be addressed before it will set up to its optimum playability.

It has a very high action with a very low saddle height, no room for adjustment there.

Its bridge is beginning to lift

On investigating the guitar’s action it becomes clear that the string height cannot be lowered at the bridge saddle and the only repair solution will be a neck reset. The bridge will need to be removed and re-fitted.

The Neck Removal and Reset

The 15th fret is removed

The fingerboard extension is heated and loosened

A hole is drilled through the vacant fret slot into the dove-tail cavity

The lacquer is scored around the heel

The neck is fitted into a Neck Removal Jig. Steam is pumped into the join to soften the glue

Herein lies a problem; this bridge (for some unknown reason) has been inlayed into the soundboard. This could be a reason as to why the bridge has begun to lift and will need to be remedied before the bridge can be refitted.

Take a closer look at the internal image; the bridge-pin holes (through the soundboard and into the bridge-plate) have become distorted. This could cause a problem when trying to re-stringing the guitar as the bridge-pins will not seat correctly.

The solution is to inlay a soundboard patch to restore the soundboard height and to repair the distorted pin holes

The Soundboard Repair

The area under the bridge is levelled and cleaned up

The pin holes are drilled out and fitted with new Spruce

The scratchplate is removed for ease of working

A soundboard patch is made up from Sitka Spruce, glued into place and trimmed to thickness

The underneath of the bridge and soundboard patch are gently heated to extend the open time of the Hide Glue

The Hide glue is applied and the join is clamped and left overnight

The hole in the fret slot is plugged and re-sawn

The scratchplate is replaced

The 15th fret is replaced

A new bone nut is made and the guitar is re-strung and tested for correct intonation